(1) Field of the Invention
This invention relates to drying natural gas by removing water and/or sulfur compounds from wells, transmission lines, gathering stations, and the like.
(2) Description of the Prior Art
Apparatus and methods heretofore used for drying natural gas are generally concerned with the exposure of the moisture carrying gas to trays of glycol such as illustrated for example in U.S. Pat. No. 4,070,231.
Similar devices are found in U.S. Pat. No. 3,664,091 and are referred to in U.S. Pat. Nos. 3,864,103 and 4,010,009.
A somewhat different device for removing water from natural gas may be seen in U.S. Pat. No. 3,322,411 wherein a generally horizontally disposed fluid flow passage is filled with a porous material, wet gases directed therethrough and glycol is introduced at intervals therealong.
The prior art devices are usually of fixed design and related in size to the particular flow volume of a gas well and the prior art units are generally unable to remove water and contaminants from the gas stream beyond the point of equlibrium in that they cannot remove more water than the glycol is able to absorb.
The present invention will remove water beyond the point of equilibrium due to the injection of the triethylene glycol into the high speed gas stream and the arrangement which permits an expansion in a turbulent flow in a mixing zone with the resulting extremely high surface to mass ratio and a resulting high degree of interpenetration of water and glycol.
Additionally the apparatus and method result in the cooling of the gas stream in a refrigeration and change of pressure effect, all of which contribute to a superior drying action.
The present method and apparatus can be varied to match various flow volumes and pressures by merely changing the triethylene glycol injection nozzles thus rendering the invention readily adaptable to many situations.